Spark plug question. 41-985 vs 49-110

I am going to change the plugs in my 2005 yukon xl. The manual calls for a AC 41-985 iridium but the plugs that all of the parts stores list is a AC 41-110 iridium. Does anyone know the difference between the two? I can not find the 985 anywhere. Thank you in advance for sharing your thoughts

I am going to change the plugs in my 2005 yukon xl. The manual calls for a AC 41-985 iridium but the plugs that all of the parts stores list is a AC 41-110 iridium. Does anyone know the difference between the two? I can not find the 985 anywhere. Thank you in advance for sharing your thoughts

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Mike.....there's no difference between the A/C 41-985 and the A/C 41-110 they are the Same Plug........G.M. Changed the Part Number to the A/C 41-110,

Thanks Mike. I was hoping that you would respond as it seem like you always have the info when it comes to GM parts!

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Glad to help Mike, and regarding the Gap on the New Plugs, below is from a G.M. Service Bulletin,

PARTS INFORMATION:A New Spark Plug has been released for use in the above vehicles. The New Spark Plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The New Spark Plug, A/C Delco Iridium Part Number 41-110, is Gapped to 1.01mm (0.040 inches) when the Spark Plug is made. The Spark Plug Gap is set during Manufacturing and should Not be Changed to the Gap required with the Platinum plug, orDamage to the Spark Plug may result.

I pulled out 3 plugs a few minutes ago. They came out easily. They look new and the gap is .038". So, looks like I have to start investigating other causes of my sudden MPG decrease. Thanks again for the info